Satellite communication devices are gaining increased use in many application areas. Such devices are now being used in over-the-highway truck fleets to allow greater communication between the truck driver and a fleet base operator. The devices generally allow data related to the truck performance and characteristics to be communicated on demand, or at automatically timed periodic intervals.
A highway truck requires an antenna to receive and to send various types of electromagnetic frequency signal. Conventionally, a truck may use a first antenna to receive and to send satellite signals, and a separate second antenna to receive commercial radio or CB signals. Alternatively, if a common antenna is used, an additional filter box is required to filter out the frequency band required by the satellite communication system. The dramatic increase in the number of communication devices used by a highway truck operator has increased the complexity of these types of systems. In today's application environment, a single truck may receive numerous signals at any one time, e.g., commercial AM/FM radio, satellite, CB radio, weather, GPS or cell phone.
The frequency of these various signal types varies. Commercial AM radio bands have a comparatively low frequency range of 550 to 1600 kHz. Commercial FM radio operates in the 88 to 108 MHz range. Citizen Band radio frequencies are in the relatively narrow range of 26.95 to 27.405 MHz. Cellular telephone operates in the relatively high frequency band of 825 to 890 MHz. Weather band signals have frequencies ranging from about 150 MHz to about 170 MHz. Satellite communication signals may have frequencies ranging from about 130 MHz to about 150 MHz. Because of the wide range of frequencies discussed, at least one separate, external filter box is normally utilized to discern the frequency used for satellite communications distinguishing it from other frequencies. Further, additional hardware, connectors, and cabling is required for each extra filter unit installed.
One object of the present invention is the elimination of conventional hardware. The elimination of any part in a standard truck bill of material is significant in not only the cost of the truck, but also in the operation of an over the highway truck fleet. Whenever a part is removed from the bill of material of a truck, the overall weight of the truck reduces. A relatively small reduction in the overall weight of a truck can translate to a material annual fuel savings for a fleet operator.
A need in the market exists for a reliable and relatively inexpensive apparatus and method to accurately receive and send satellite communication signals without increasing truck bill of material complexity, assembly time, or overall system costs.